<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>圆角边框的理解与应用</title>
		<style>
			div {
				width: 300px;
				height: 300px;
				background-color: red;
				border-radius: 10px;
			}
			.yuan {
				width: 300px;
				height: 300px;
				background-color: red;
				border-radius: 150px;
			}
			.changfangxing {
				width: 300px;
				height: 100px;
				background-color: red;
				border-radius: 50px;
			}
			.fuhe {
				width: 300px;
				height: 300px;
				background-color: blue;
				border-radius: 10px 20px 30px 40px;
				/* border-top-left-radius: ; */
				
				
			}
		</style>
	</head>
	<body>
		<div></div>
		<div class="yuan"></div>
		<div class="changfangxing"></div>
		<div class="fuhe"></div>
	</body>
</html>